Well, if it's definitely out of place (e.g., you can run your finger carefully across the seam between panels and feel it change drastically), you should ask your dealer or ask a GM rep if such things are covered by warranty. If you want to be extra sure, you could keep an eye on it for another few months and if it gets worse (document with photos well), you stand a better chance convincing them to fix it. You still have 33 months of bumper-bumper warranty to see if it becomes an issue.
Oh, and to actually answer your question, no, I don't see anything like your photo nor did I feel any loose trim pieces using my finger test. I did, however, noticed that the rear-left tail light assembly appears not tightly aligned as the rear-right one. I'm keeping an eye on it...